Circuit-breaker.



H. A. STEEN.

CIRCUIT BREAKER.

APPLICATION FILED MAR- 23. 1912.

Patented Jan. 9, 1917.

H IE 24 x I 25 /z/ /4 I v g WWW/m /vwwxmf HALFDAN A. STE-EN, OF NORWOOD OHIOv A SSIGNOR, BY MESNE ASSIGNMENTS, TO

ALLIS-CHALMER$ MANUFACTURING COMPANY, A CORPORATION OF DELAWARE.

CIRCUIT-BREAKER.

Specification of Letters Patent.

Patented Jan. 9, 1917.

Application filed March 23, 1912. Serial No. 685,715.

To all whom it may concern Be it known that I, HALFDAN A. STEEN, a subject of the King of Norway, residing at Norwood, in the.county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Circuit-Breakers, of which the followingis a full, clear,

and exact specification.

My present invention relates to circuitbreakers.

In modern high potential electrical transmission systems special protective apparatus is required, as the ordinary circuit-breakers are not adapted to provide a separation between their terminals sufficient to break the arcs which form. Moreover, the ordinary circuit-breaker is so slow in acting that it allows current to continue long enough to defeat the object of the circuit-breaker.

It is the object of my invention to provide an arrangement whereby, under abnormal conditions, an electric circuit will be interrupted sufficiently quickly and by a break sufficiently wide to prevent a continuance of the current for any appreciable time.

It has been found that the pressure generated by the blowing of an inclosed fuse is almost explosive in its nature, the pressure instantaneously produced in the fuse chamber often being enormous. In my device I aim to use the pressure suddenly developed bythis blowing of the fuse to move to off position a switch arm which normally ep; gages stationary contactsfor completing a circuit, thus obtaining an almost instantaneous interruption of the circuit. The various novel features of my invention will be apparent from the description and drawings, and will be particularly pointed out in the claims.

This invention is illustrated in the single figure of the drawing, which is a side elevation partly in section, of the preferred form.

Mounted upon a suitable insulating panel or support 10 are two stationary contacts 11 and 12 which are normally conneted by a movable switch arm 13. This movable switch arm 13 is preferably pivotally mounted in the stationary .contact member 11. The main body portion .of this movable switch arm comprises an insulating member. 14 having a hollow portion 15 and an opening 16 which is formed in the curved pro jection 17 of said member 14. This insulating member is provided at its ends with threaded portions 18 and 19 by means of which metal caps 20 and 21 are secured thereto. The metal cap 20 is provided with a projection 22 which forms the pivotal connection at 23 with the stationary switch contact 11, and the metal cap 21 is provided with a knife blade projection 24 which normally engages the stationary, contact 12. Interposed between each cap and the ends of the insulating member 1 1 are metal disks 25 which are in electrical contact with the metal caps and to which a fuse 27 is elec trically connected, by any suitable means, such as solder 26. This fuse occupies the central portion of the hollow switch arm 13, and forms an expulsion fuse. Adapted to receive the curved projection 17 and to nor mally close or cover the opening 16 is a curved socket member 28 which is secured to the panel 10.

When the movable switch member 13 is in its normal position, as here illustrated, with the movable contact member 24 engaging the stationary contact member 12, the circuit is completed through terminal 29, stationary contact 11, projection 22 of cap 20, lower metal disk 25, fuse 27, upper metal disk 25, knife blade contact 24 of cap 21, stationary contact 12 and terminal 30.

In case of an overload, whether the current be alternating, pulsating, or direct, the fuse 27 blows. Since the fuse is in the comparatively small space of the hollow movable switch arm 13, which has but one main outlet or opening 16, a comparatively great pressure is generated by the blowing of the fuse and exerts itself through this opening upon the socket member 28, violently forcing the movable contact member in a counter-clockwise direction and out of engagement with the stationary contact member 12. This movement of the movable switch memberin a counter-clockwise direction is quickly and violently made, causing a nearly instantaneous separation between the movable switch member 13 and stationary contact 12. This separation is great enough to prevent any continuance of the current and sudden enough to prevent any damage before the circuit-breaker has operated. In order to prevent any damage to the movable switch arm 13, a buffer spring 31 is provided to catch said switch arm.

There maybe various modifications in the precise arrangement here shown and described, and I intend to cover all such modifications which do not involve a departure from the spirit and scope of my invention as set forth in the appended claims.

What I claim as new is:

1C In a circuit breaker, the combination of fixed contacts, a movable switch arm normally engaging said contacts, said switch arm having a hollow portion with an opening, stationarily mounted means efi'ective to cover said opening when said switch arm is in circuit-closed position, and a fuse in the hollow portion of said switch arm, pressure created on the blowing of said fuse acting against said covering means to throw said switch arm out of engagement with one of said contacts.

3. In a circuit breaker, the combination of a movable switch member, a fuse inclosed within said movable switch member, and means forming a' stationary abutment against which fluid pressure created on the blowing of said fuse is exerted directly and reacts to cause a, movement of said movable switch member.

I. In a circuit-breaker, the combination with a movable switch member having a hollow portion and provided with a curved pro ectlon with an opening, a curved member mounted on a stationary support and adapted to receive said curved projection and to pover said opening, and a fuse in the hollow portion of said switch member which when blown generates pressure which is exerted between said movable switch member and covering member for actuating said switch member.

5. In a circuit-breaker, the combination of stationary contacts, a movable switch member comprlsing a hollow member having an opening, metal caps for the ends of said hollow member, said caps being engageable with said stationary contacts, and a fuse in the hollow member electrically connecting said caps to complete a circuit through said stationary contacts and said movable switch member, and means for covering said open- -ing, said covering means being mounted on a stationary support and cooperating as an abutment with said movable switch member 'bination of a plurality o rename to utilize the pressure generated by the blowcurved portion and to cover. said opening,

and an expulsion fuse carried in the hollow portion of said movable contact member and which when blown generates pressure which is exerted between said movable contact and socket for actuating said movable contact.

7. In a circuit-breakena hollow movable switch member having a projection with an opening, a member with which said projection telescopes, said latter member being mounted on a stationary support, and a fuse in the hollow portion of said switch member which when blown generates pressure which is exerted between said switch memberand member with which said projection telescopes to cause a movement of said switch member.

8. In a circuit-breaker, the combination of a hollow switch member having an opening, an element with which said switch member is operatively associated, said element being immovably mounted on a stationary support, and a fuse in the hollow portion of said switch member which when blown generates pressure which is exerted between said 'switch member and said element to caus movement of said switch member.

9. In a circuit-breaker, amovable switch acting on said covering. member to cause actuation of said switch member.

10. In a circuit-breaking device, the comcooperative contacts one of which is movable toward and away from the other, supports for said contacts, the support for a movable one of said contacts comprising a hollow portion, a fuse contained in said hollowportion, an abutment carried by and immovable relatively to the support for the other of said contacts, said abutments being operatively associated with a portion of said fuse-carrying'support whereby pressure created on the blowing ofv said fuse is exerted directly upon said abutment to cause movement of one of said contact-carrying supports relatively to the other.

11. In a circuit-breaker, a pair of cooperative, relatively -movable switch members, supports for said switch members, the support for a movable one of said switch meme 13 bers being provided with a fuse-containing recess having an opening to the outside of said member, and a member immovably mounted on the support for the other one of said switch members and adapted to cover the opening in the support for said first switch member when the latter is in one position, pressure created on the blowing of said fuse acting on said covering member to cause actuation of said movable switch 10 member.

In testimony whereof I afiix my signature, in the presence of two witnesses.

Milwaukee, Wis, Feb. 27, 1912.

HALFDAN A. STEEN. Witnesses:

LOUIS G. NICHOLS, FRASER JEFFREY. 

